INSTALLATION INSTRUCTIONS
14
3.5 Water connections
In order to safeguard the heat exchanger and
circulation pump, especially in case of boiler
replacement, it is recommended that the
system is hot-flushed to remove any impurities
(especially oil and grease) from the pipes and
radiators.
Make sure that the domestic water and central
heating pipes are not used to earth the
electrical system. The pipes are totally
unsuitable for this purpose.
Isolation Valves must be installed on the
heating and D.H.W circuits. This will facilitate
all maintenance and service operations where
the boiler needs to be drained.
■
To prevent vibration and noise coming from
■
the system, do not use pipes of reduced diameter,
short radius elbows or severe reductions in the cross
sections of the water passages.
■
To facilitate the installation, the boiler is supplied with
an hydraulic connection kit (see fig.2).
Domestic hot water circuit
■
In order to prevent scaling and eventual damage to
the D.H.W heat exchanger, the mains water supply
must not have a hardness rating of more than 17.5
°Ck. It is nevertheless advisable to check the
properties of the water supply and install the
appropriate treatment devices where necessary
.
The cold water supply pressure at the inlet to the
boiler must be between 0.5 and 6 bar.
In areas with higher water inlet pressure a pressure
reducing valve must be fitted before the boiler.
The frequency of the heat exchanger coil cleaning depends on the hardness of the mains water supply and the
presence of residual solids or impurities, which are often present in the case of a new installation. If the
characteristics of the mains water supply are such that require it to be treated, then the appropriate treatment
devices must be installed, while in the case of residues, an in-line filter should be sufficient.
All D.H.W. circuits, connections, fittings, etc. should be fully in accordance with relevant standards and water supply
regulations.
Guidance G17 to G24 and recommendations R17 to R24 of the Water Regulation Guide.
Central heating circuit
In order to prevent scaling or deposits in the primary heat exchanger, the mains supply water to the heating circuit must be
treated according to the requirements of local standards.
This treatment is indispensable in the case where the circuit is frequently topped-up or when the system is often either partially
or fully drained.
The outlet connection of the boiler safety valve must be connected to a discharge trap. The manufacturer will not be
held responsible for flooding caused by the operation of the safety valve in the case of system overpressure.
140
12
0
RC
HR
CWI
G
HWO
HR
27
2
74
102
80
70
78
86
Fig. 1
HWO
HF
CWI
G
HR
Fig. 2
Summary of Contents for RK 25 /B
Page 2: ......
